Tanshinone IIA suppresses fibrosis induced by high glucose conditions in HK-2 cells via inhibition of extracellular matrix deposition, reduction of oxidative stress, and inhibition of epithelial to mesenchymal transition

Abstract

Purpose: To investigate the anti-fibrotic effects of tanshinone IIA (TS) on renal tubular epithelial cells (HK-2 cells) under high glucose conditions and their related molecular mechanism(s) of action.Methods: After treatment with TS (6 μg/mL) for 24 h, the morphology of HK-2 cells stimulated by high glucose was observed under the microscope. Additionally, potential mechanisms related to the antifibrosis effects of TS were evaluated using western blotting assay and quantitative real time PCR (qRTPCR), including transforming growth factor (TGF) β1, α-smooth muscle actin (α-SMA), heme oxygenase 1 (HO-1), laminin (LN), fibronectin (FN), and E-cadherin (E-cad).Results: A high-glucose culture environment induced fibrosis of HK-2 cells, as indicated by changes in cell morphology. The anti-fibrotic effects of TS were mainly associated with a decrease in the expression levels of TGF-β1, α-SMA and LN, while the expression of E-cad increased. These resultsalso revealed that TS increased the expressions of HO-1.Conclusion: The findings suggest that TS suppresses fibrosis caused by high glucose in HK-2 cells by inhibiting extracellular matrix deposition and epithelial-mesenchymal transition and by reducing oxidative stress. Further investigations are needed to evaluate the clinical application of this compound in diabetic nephropathy. Keywords: Tanshinone IIA, Diabetic nephropathy, HK-2 cells, Fibrosis